1. Field of the Invention
The present invention relates to digital image photography in apparatuses, including digital cameras as well as mobile terminals equipped with camera modules, and more particularly to a method for photographing a panoramic image.
2. Description of the Related Art
Conventionally, an image capture unit in a digital image photographing apparatus can obtain an image formed within a focal length of a lens thereof. Here, the obtained image is within a range of the viewing angle (between about 30° to 50° for general cameras), which is smaller than the human visual angle (between about 150° to 200°). There is a conventional method of photographing multiple images while properly changing the viewing angle, and inter-connecting the photographed images in sequence to reorganize them into one consecutive image. Thus, one can obtain a picture with a viewing angle similar to or larger than the human visual angle. This method is called a panoramic image photographing method.
In a panoramic image photographing mode, the conventional digital image photographing apparatus photographs several images that are inter-connected horizontally or vertically and then stores them in a memory. The images stored in the memory are provided to an appropriate interior/exterior image processor later, and are inter-connected into one consecutive image. In order to eliminate color differences and image discords at the boundaries between the images, digital image photographing apparatuses photograph multiple images with sufficient overlap between their boundaries, and then align the images by adjusting their boundaries. Thereafter, they perform image processing, including stitching and bending. Through this process, a single image including naturally inter-connected multiple images is obtained.
Alignment accuracy is a high priority in photographing a panoramic image. To this end, an accessory apparatus, such as a tripod, is usually used in manual photographing by a user. Recently, a method has been suggested in which a corresponding photographing apparatus is mounted on a tripod or the like, and the mounted photographing apparatus is rotated according to respective images in panorama photographing. An example of such the method is disclosed in Korean Patent Application No. 2003-0052444 filed on Jul. 29, 2003, entitled “Camera And Method for Photographing Panorama Picture” filed by Samsung Techwin Co. Ltd., and the inventor is BAE, Sung-cheol. Further to the above-described methods, an apparatus that can detect rotation angle may be additionally mounted on the corresponding photographing apparatus. A user sets the rotation angle of the photographing apparatus in advance. Therefore, the respective images are photographed by rotational displacement over the rotation angle of the photographing apparatus pre-set by the user in panorama photographing. This method has been also suggested.
Furthermore, in order to align the respective images more accurately when photographing panoramic images without a mounting accessory or additional hardware on the corresponding photographing apparatus, another method has been proposed. The method provided uses the partial region of the border of previously photographed image is represented appropriately overlapping with the current image for photographing when photographing respective images. Thus, the user can control an appropriate position for photographing by adjusting the pre-photographed image with the current photographing image. An example of such the method is disclosed in US Publication No. 2004/0189849 filed on Mar. 31, 2003, entitled “Panoramic Sequence Guide” in the name of an inventor, Gregory V. Hofer.
Photographing the panoramic image requires more user's sophistication and proficiency vis-a-vis photographing a general single image. This has necessitated better and more convenient solutions for manipulating and photographing images.